Variable escapement device



Nov. 30, 1965 R. A. HIGONNET ETAL 3,220,531

VARIABLE ESCAPEMENT DEVICE 2 Sheets-Sheet 1 Original Filed June 8, 1956 vwm I INVENTORS RENE A. HIGONNET LOUIS M. IVIOYROUD Nov, 30, 1965 R. A. HIGONNET ETAL. 3,229,531

VARIABLE ESCAPEMENT DEVICE a Sheets-Sheet 2 Original Filed June 8, 1956 INVENTORS HIGONNET MOYROUD RENE A LOUIS M. BY

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United States Patent 3,220,531 VARIABLE ESCAPEMENT DEVICE Rene A. Higonnet, Cambridge, and Louis M. Moyrond,

West Medford, Mass. (both Photon, Inc., 355 Middlesex Ave., Wilmington, Mass.)

Continuation of application Ser. No. 856,061, Nov. 30, 1959, which is a continuation of application Ser. No. 590,304, June 8, 1956. This application Aug. 5, 1964, Ser. No. 388,749

Claims priority, application Great Britain, Aug. 2, 1955, 22,213/55 34 Claims. (Cl. 19784) The present invention relates to variable escapement devices, and more particularly to such devices adapted for intermittent, measured, progressive movements to ef feet the displacement of an output member, and the repeated return of said member to a predetermined initial position. This application is a continuation of our copending application Serial No. 856,061, filed Nov. 30, 1959, now abandoned, which was a continuation of Serial No. 590,304, filed June 8, 1956, now abandoned.

The invention comprises an improvement upon the variable escapement and related controls disclosed in our application Serial No. 375,653 filed Aug. 21, 1953, now Patent No. 2,806,574.

An object of this invention is to provide an escapement device to effect the desired variable spacing of the characters and words in a line of type by successive, intermittent movements of a spacing carriage. The carriage may be of any suitable form adapted for spacing the characters, for example a film carriage like that of our Patent No. 2,790,362, but it is preferably a prism carriage like that of Patent No. 2,670,665 to Caldwell. Both of these examples relate to photographic type composition, but it will be obvious that other applications are within the purview thereof.

Hitherto, such intermittent spacing mechanisms have been subject to objectionable vibrations and bouncing, giving rise to speed limitations due to the inherent difficulty of rapidly accelerating and arresting a carriage having appreciable inertia. It is accordingly another object to improve the speed and smoothness of the mechanism.

A further object in type composition is to provide resetting means for the escapement device and return means for the carriage actuated thereby after each line is photographed.

A still fnrther object is to provide means for checking each line after it is photographed to ascertain whether it has been justified, and to correct the position of the variable escapement to prevent a failure thereof in one line from being carried forward to successive lines.

With the above and other objects in view, the features of the invention comprise the variable escapement and the resetting and justification checking circuits and controls as hereinafter shown and described.

In the drawings, FIG. 1 is a partially schematic side elevation of the variable escapement and character spacing carriage according to a preferred embodiment of the invention.

FIG. 2 is a schematic circuit diagram of the controls for the escapement of FIG. 1 including the resetting and justification checking circuits;

FIG. 3 is a fragmentary view of FIG. 2 illustrating a position wheel; and

FIG. 4 is a view of an alternative form of justification checking device.

Referring to FIG. 1, there is provided a binary differential gear escapement 12 similar to that described in said application Serial No. 375,653. However, the individual drives for the stages are different, being friction drives in place of the spring drives disclosed therein. The device as shown in FIG. 1 is to a degree schematic in arrangement, proportions and details of design, but it will be understood that this is to permit a ready understanding of its operation. In actual construction the parts will, of course, be oriented in such suitable manner as may be dictated by considerations well known to those skilled in the mechanical arts.

The various parts of the mechanisms are supported between the end walls of a rigid frame 14. In this frame are journaled a set of eight interconnected differential stages D1 to D128, each stage representing one digit of a binary input value. The left-hand differential represents the lower order digit. There is an input wheel such as E1 to E128 and an output shaft such as P1 to P128, for each dilferential. There are also seven carry-over gears 16, 18, 20, 22, 24, 26 and 28 by which the motionof each output shaft is transferred to a carry-over input gear T2 to T128, respectively, of the next higher order dilferential. Thus for example, the motion of the output shaft P8 is determined by both the directly applied input rotation of the wheel E8 and by the carry-over motion imparted by the output shaft P4 through the gear 20. A gear 29 is held fixed by a locating pin 29' since there is no carry-over to the lowest order stage. The pin 29' permits very fine original adjustment of the zero position of the escapement, and also adjustment to compensate for wear.

The gear ratios throughout each differential mechanism are 1:1, which produces a binary series because the carry-over rotation is scaled down in the differentials by a factor of 2.

The mechanism is actuated by applying intermittent equal angular displacements to selected combinations of the wheels E1 to E128 according to the binary values of the variable space widths of the characters in the line. As described in said application Serial No. 375,653, the type composing machine is provided with storage means, by which information corresponding to the characters and their widths is committed to a memory device and the justification requirements ascertained, and also with transcription means constituted by character photographing apparatus for projecting the characters one at a time on to a film, the characters being spaced and justification space increments inserted after each projection by the variable escapement. To this end, a set of escapement magnets M1 to M128 (FIG. 2) is provided. The armatures of these magnets are provided with rockers A1 to A128, each having a pair of pawls such as 30 and 32 pivoted on the rockers and alternately engageable with the wheels E1 to E128. The rocker A128 is an exception in that, while a pawl 34 thereon arrests the wheel E128 to prevent its rotation in the normal direction indicated by the arrow and permits such rotation only when the rocker A128 is actuated, it permits rotation in the reverse direction to allow return of the output mechanism as described below. Details of the pawl mechanisms are not further shown, being well known in the art.

Referring to FIG. 1, a continuously rotating motor 36 is secured to a shaft 38 journaled in the frame 14. A gear 40 is secured to this shaft and engages a train of eight gears pivotally supported on the shafts P1 to P128. These latter gears provide friction drives F1 to F128 for the output shafts P1 to P128, subject to the operation of the escapment magnets M1 to M128. The friction drives are identical and are exemplified by the drive for the shaft P1. A gear 42 is supported on this shaft opposite a disc 44 having a suitable friction material 46 supported thereon. The disc 44 is free to slide longitudinally on the shaft. A disc 48 is secured to the shaft, and a compression spring 50 bearing on the latter disc urges the disc 44 against the gear 42. The disc 44 is constrained Patented Nov. 30, 1965 3 from rotation with respect to the disc 48 by a pin 52 secured to the former and received in a hole in the latter as clearly illustrated. It will be observed that the drives for the consecutive stages alternate in direction. This is indicated by the arrows on the wheels E1 to E128 in FIG. 2.

It will be understood that the total of the binary width values sent to the escapement magnets M1 to M128 for each hne to be justified equals the justified line length as described in the before-mentioned applications and patent. The circuits for energizing the magnets are preferably of the form described therein and may include a register and circuits connected with the justifier. For present purposes, these circuits are represented by contacts R1 to R128 which are closed briefly in successive selected combinations representing each successive character, word and justification increment space to be inserted in the line.

The characters are projected by a flash lamp 54 on to a sheet of sensitized film carried by a support 56 substantially as described in the above-mentioned Patent 2,670,- 665. As there described, the characters are supported in a circle on a continuously revolving disc 58. Means for energizing the flash deivce (not shown) are provided with timing means to cause the flashes to occur at the precise instants in which selected characters are in a projection position. The character images are projected through a fixed collirnating lens 60 to a converging lens 62 carried on a movable support 64. The converging image is reflected by a right-angle reflector 66 on to the film. The support 64 is secured to a rack 68 slidable in an extension of the frame 14. A coil spring 70 is secured to an end of the rack and passes over a pulley 72 to a spool 74. This spring urges the rack in the direction appropriate for spacing the characters from left to right. The rack is arrested by a gear 76 engaged therewith and secured to the shaft P128.

In addition to the foregoing parts, the sliding prism mechanism includes a set of brushes 78 shown at the upper right in FIG. 2. These brushes bear upon a code plate 80 having conducting segments arranged as shown in FIG. 2. Also, a switch 82 is situated in position to be opened by the return of the sliding prism to a position at -or near the left-hand margin of the line.

The foregoing description includes those parts of the apparatus employed in spacing the characters in a line. In addition to this function, it is necessary to reset the escapement and return the sliding prism after each line is photographed. It is also desired to provide a means for determining whether the line has been justified and for sounding an alarm if the justification isnot correct. To this end we provide a sequence switch 84 adapted to step from the position shown to positions a, b, c, d and e in that order. The sequence is initiated after the spacing movement for the last character to be photographed. The circuits thus closed perform the required functions as hereinafter more fully described.

The mechanical parts of these additional controls include position wheels S1 to S128 secured to the shafts P1 to P128, respectively (FIGS. 1 and 2) and a return clutch 86 for the sliding prism, the clutch having a clutch magnet 86'. The position wheels have cam surfaces with alternate, equal peaks and dwells in which ride cam rollers such as 88. These rollers are mounted on the blades of transfer spring contact sets C1 to C128 having contacts which are alternately connected with the blade as it moves from a peak position to a dwell position. The dwell positions represent the 0 digits and the peak positions as illustrated in FIG. 3 represent the 1 digits in binary notation. In FIG. 2, the escapement is shown with all stages in the 0 position. A full movement from a 0 position as shown in FIG. 2 to a 1 position as shown in FIG. 3, or vice versa, is produced by a normal escapement of one tooth of the escapement wheel for the corresponding stage. This is due to the fact that the numher of teeth on the escapement wheel equals the number of peaks or dwells on the position wheel, and an escapement of one tooth of the escapement wheel produces a rotation in that wheel of twice the angle that is produced in the corresponding P-shaft through the differential gearing.

It will be observed that the position wheel S1 is always exactly in either the 0 position (FIG. 2) of the 1 position (FIG. 3). However, because of the binary relationship of the stages anymotioii of an output shaft which is transmitted through rotation of a carry-over gear to a stage of higher order produces in the latter stage only one-half its own amount of angular rotation. For this reason the position wheels S2 to S128 may be in any one of several additional positions intermediate the O and 1 positions, whereby the corresponding contacts may be either closed, opened, or only partially closed. But, as will be shown below, the controls are not effected through the partially closed contacts and no error in operating can result therefrom.

In FIG. 2, the input relays B1 and 13128 of a binary line length accumulator are illustrated. This accumulator is preferably of the generaltype described in our Patent No. 2,682,814, arid p ovides a means for measuring in binary notation the line dificitf or space to be divided into justification increments. The accumulator also has stages corresponding to the binary values 256, 512, 1024 and 2048, not shown. Prior to storage of a new line of characters as heretofore described, the operator closes a combination of justified line length selection keys K1 to K2048 to enter in the accumulator an initial value determined by the number of units in the desired justified line length. The method by which the keys are selected may be described as follows. The value c for the variable escapement, or the stages B1 to B128 of the accumulator corresponding thereto, is defined as the numerical value of a carry-over from the highest order stage thereof, in this case 256. The value a for the stages of the accumulator above the stage B128 is defined as the total numerical value represented by these stages if each represents the digit l, attributing the value 1 to the lowestorder stage (e.g., the stage having the value 256). Thus in the illustrated case the value a is 15 for the four stages assumed. The justified line length j is defined as where n and m are integers and m is less than c. The keys K1 to K128 which are closed are those which represent in binary form the value cm1. The keys K256 to K2048 which are closed are those which represent in binary form the value (a-n)c.

If we take, for example, a desired, justified line length i of 1867 units, we find that n=7 and m=75. The keys K4, K16, K32 and K128 representing 180 are closed, and the key K2048 representing the value 2048 is closed.

It follows that if, during the selection of characters in the line, the accumulated total width value thereof should equal j the accumulator stages would represent the value which is that value which the accumulator would represent if all stages were ls. The existence of this condition is useful to the operator in determining when to stop the storage of characters in a given line, and is fully described in our copending application Serial No. 531,023,, filed Aug. 29, 1955.

The keys K1 to K2048 remain closed throughout the storage and photography of the line, and are again utilized to check the accuracy of the justification. The first. step after the line is photographed, as previously explained, is to move the switch 84 to the position a. This. energizes a relay 90 (FIG. 2) which closes make contacts, to connect a voltage through each of the closed keys. K1 to K128 to energize the corresponding escapement,

magnets M1 to M128. If the line was correctly justified, the escapement will already have moved through a total of 1' units, and the additional displacement brings the total to j+(cm1)=(n+1)c1 units.

The switch 84 then steps to position b, which connects a voltage to the magnet M1 to bring the total in the escapement to (n+l)c. The escapement has now been brought to a total displacement equal to the smallest multiple of its capacity within which the given j'ustified line could be fitted. Furthermore, the escapement stages are each at 0, provided the justification is correct.

The switch 84 then steps to position 0, thus energizing a relay 92. This relay connects a voltage to the brushes 78 which have now moved a distance equal to the value (n+l)c over the card 80. The conducting segments on the card are located so that the lowest brush comes to rest on the left hand segment of the lowest row of segments if n=1, on the next segment if n=2, and so on. The value represented by the depressed keys K256 to K2048 is, as previously stated, (a--n)c. The code areas on the card are so related to the keys K256 to K2048 that the brushes find a circuit to a lead 94 unless they are in the position indicated. Thus if n=l the lowest brush will have come to rest on the first segment in the lowest row and a circuit exists unless all keys except K256 are closed to represent the value (a-1)c, and so on. In the previously given example, the brushes will have come to rest on the seventh segment as indicated by the dash lines, but will find no circuit to the lead 94 since the key K2048 alone is depressed.

The lead 94 is connected With a relay 96 and with an alarm device such as a buzzer 98. The relay holds on its own make contacts to sustain the alarm until released by the opening of a key 100.

The switch 34 then steps to the position at and energizes a relay 102. Make contacts of this relay close a circuit from a lead 104 to the buzzer 98. Also, a voltage is applied to the blade of the switch C1. This latter voltage is connected to the lead 104 to energize the buzzer unless the position wheel S1 is in position 0. If it is in position 0, the voltage is connected to the blade of the switch C2 and a similar test is applied. If all stages are at 0 the voltage is connected to a lead 106 and energizes a carriage return relay 108. This latter relay holds on its own make contacts and the contacts 82, the latter contacts opening when the carriage reaches the left margin, as previously stated (see FIG. 1). Contacts of the relay 1108 close a circuit to the clutch magnet 86'. Referring to FIG. 1, the shaft 38 of the motor 36 is secured to a gear 110 which is engaged with a gear 112 through an idler 114. The clutch magnet 86', when energized, engages the gear 112 with the shaft P128 and overpowers any friction drive thereon to reverse the shaft, deflect the pawl 34 from the path of the wheel E128, and return the prism carriage toward the initial position. This motion is interrupted by opening of the contacts 82. As a result, the shaft P128 is rotated through precisely the same angle through which it rotated during the spacing of the line. However, in contrast to the escapement of said application Serial No. 375,653, the other stages of the escapement are not similarly rotated in reverse through angles equal to those through which they turned during the spacing of the line,

It will be observed that, in position d of the switch 84, if the buzzer is energized through the lead 104 by reason of a switch C1 to C128 indicating a 1 condition, a voltage is applied to the escapement magnet of each such stage in progression whereby, after energization of the buzzer, the escapement stages are all brought to the 0 positions and the prism carriage returned. This insures the return of the carriage to the same precise starting position whether the line has been justified or not.

(The position e of the switch 84 is concerned with 6 other operations of the machine that may be disregarded for present purposes.)

The alternative justification checking mechanism illustrated in FIG. 4 can be used in place of the circuits described above, if desired. In this arrangement a sliding block 116 is used, which is secured by the operator on a rod 118 by a thumb screw 120 at a position corresponding to the length of justified line desired. The block 116 has a notch 122 into which a lug 124, which is a part of the prism carriage, can fit with little play. At the end of a line the rod 118 is moved through a suitable mechanism, not shown, so that it remains parallel with itself and reaches a position indicated by dash lines 126. If the lug 124 engages the notch 122 after the displacement of the rod 118, contacts 128 are opened. These contacts may be connected in the buzzer circuit in any suitable manner to provide an indication of the existence of correct justification, or its absence, as desired.

In summary, it will be seen that the stages below the l28-level comprise a spacing mechanism which is not reversed during the return movement of the prism carriage. Instead these stages are under a control which becomes effective after the line has been spaced by the desired succession of spacing movements, and this control advances them until they have moved by a multiple of the small increment represented by the movement of the lowest-level stage. In the described example this multiple is a multiple of 128. As a result, when the prism carriage is ready to space the next line, the escapement itself is in a zero position corresponding to the margin of the page. Also, any backlash in the stages of the spacing mechanism which comprises the stages below the l28-level does not have to be taken up again before the new line is started.

A further feature of the variable escapement as shown in FIG. 1 is an additional friction drive on the shaft P128. This drive is operative in the same direction as the drive F128. It consists of a gear 130 secured on the shaft 38, a gear 132, wheels 134 and 136, friction means 138 and a spring 140, all substantially similar in construction to the friction drives F1 to F128. However, the ratio of the gears 130 and 132 is preferably such that this drive is slower than the drive F128, and the torque exerted thereby is appreciably greater. We have found that this arrangement materially improves the speed and accuracy of the escapement, tending to reduce vibration and bouncing due to rapid acceleration and deceleration of the prism carriage and related parts. We therefore achieve a smooth and rapid operation.

It will be appreciated from the foregoing that there has been provided an improved variable spacing mechanism and related controls especially but by no means exclusively suitable for photographic type composing apparatus. By these means rapid smooth and accurate spacing movements are effected, and the spacing carriage returned to its original position with precision. Means are also provided to check the justification, to give an indication if it is not correct, and to insure that any error of the spacing carriage position is not carried over to a succeeding line.

While the invention has been described with reference to specific embodiments, it is not strictly limited thereto, but also encompasses within its spirit and scope such variations and modifications of design and structure as would occur to one skilled in this art upon a reading of the foregoing specification.

Having thus described the invention, we claim:

1. A variable escapement mechanism having, in combination, a number of stages arranged in a series, each stage comprising a differential device having two input members and an output shaft, at least one of said stages having an input member connected with the output shaft of the preceding stage in said series, escapement meansto advance an input member of each stage by equal intermittent movements, contact means for each stage, and means secured to each output shaft to operate the Contact means for each alternate movement of said shaft, said contact means forming a closed series circuit when the stages are each simultaneously in one predetermined alternate displacement, and each contact means forming a connection from said series circuit to its escapernent means when its corresponding stage is not in said predetermined alternate displacement.

2; A variable escapement mechanism having, in combination, a number of stages arranged in a series, each stage comprising a differential device having two input members and an output shaft, at least one of said stages having an input member connected with the output shaft of the preceding stage in said series, escapernent means operable to advance an input member of each stage from an initial position by equal intermittent movements, and return means for the mechanism including means to operate the escapement of each stage to bring its total of displacements to an even integer, and mechanism to rotate the output shaft of the final stage in said series through an angle equal and opposite in direction to its total displacement from said initial position, the escapernent means for the final stage comprising a ratchet and a pawl adapted for deflection from the ratchet to allow the stages of lower order to remain stationary during said opposite rotation.

3. A variable escapernent mechanism having, in combination, a number of stages arranged in a series, each stage comprising a differential device having two input members and an output shaft, at least one of said stages having an input member connected with the output shaft of the preceding stage in said series, a friction drive for each output shaft, escapernent means operable to advance an input member of each stage from an initial position by equal intermittent movements, and return means for the mechanism including means to operate the escapernent of each stage to bring its total of displacements to an even integer, and mechanism to rotate the output shaft of the final stage in said series through an angle equal and opposite in direction to its total displacement from said initial position, the escapernent means for the final stage comprising a ratchet and a pawl adapted for deflection from the ratchet to allow the stages of lower order to remain stationary during said opposite rotation.

4. A variable escapernent mechanism having, in combination, a number of stages arranged in a series, each stage comprising a differential device having two input members and an output shaft, at least one of said stages having an input member connected with the output shaft of the preceding stage in said series, escapernent means operable to advance an input member of each stage from an initial position by equal intermittent movements, and return means for the mechanism including means to operate consecutively the escapements of those stages whose total of displacements is an odd integer, and mechanism to rotate the output shaft of the final stage in said series through an angle equal and opposite in direction to its total displacement from said initial position, the escapernent means for the final stage comprising a ratchet and a pawl adapted for deflection from the ratchet to allow the stages of lower order to remain stationary during said opposite rotation.

5. A variable escapernent device having, in combination, a differential gear assembly including two input members and an output shaft, an escapernent engaged with an input member and operable to cause limited, equal, intermittent displacements thereof, a transfer contact switch, means engaged with the output shaft to operate said switch to alternate positions on each movement of the output shaft resulting from said displacements, and a reset circuit closed by said switch in one of said alternate positions and connected with said escapernent.

6. In type composing apparatus, the combination of a variably movable carriage for spacing characters, a variable escapernent having a number of binary stages each comprising a differential, the stage of highest order being engaged with the carriage, means operable to advance the differentials selectively in consecutive combinations to advance said carriage, and return means including means to cause all differentials to reach even multiples of said advancements, and means to return said carriage to its starting position, said stage of highest order being adapted to allow said carriage to return without transmittal of a reverse movement thereto, whereby the differentials of lower order are unaffected by said return movement.

7. In type composing apparatus, the combination of a variably movable carriage for spacing characters, a variable escapernent having a number of connected stages each comprising a differential, the stage of highest order being engaged with the carriage, ratchet and pawl advancing means for each stage, means to cause predetermined displacements of said advancing means successively in selected combinations to advance said carriage, and return means including means to cause all advancing means to complete an even multiple of said displacements and means to return said carriage to its starting position, said stage of highest order having a pawl adapted for deflection from its ratchet in said carriage return and for reengagement with its ratchet upon completion of said carriage return.

8. In type composing apparatus, the combination of a variably movable carriage for spacing characters, a variable escapement having a number of connected stages each comprising a differential having a direct input member and an output member, advancing means to cause a predetermined displacement of the input member of each stage, the output member of the stage of highest order being engaged with the carriage, means to operate such advancing means in successive selected combinations to advance said carriage, and return means including means to cause all advancing means to complete an even multiple of said displacement and means to return said carriage to its starting position, the advancing means for the stage of highest order comprising a ratchet and a pawl adapted for deflection from the ratchet to allow the stages of lower order to remain stationary during said carriage return and for reengagement with the ratchet after said carriage return.

9. In type composing apparatus, the combination of a variably movable carriage for spacing characters, a variable escapement having a number of connected stages each comprising a differential having a direct input member and an output member, ratchet and pawl advancing means to cause a predetermined displacement of the input member of each stage, the output member of the stage of highest order being engaged with the carriage, means to operate said advancing means in successive selected combinations to advance said carriage, and return means including means to cause all advancing means to complete an even multiple of said displacement and means to return said carriage to its starting position, the pawl in said advancing means for the stage of highest order being adapted for deflection from its ratchet to allow the stages of lower order to remain stationary during said carriage return and for reengagement with its ratchet after said carriage return.

10. In type composing apparatus, the combination of a variably movable carriage for spacing the characters, a variable escapernent having a number of stages each comprising a differential having a direct input member and an output member, said differentials being connected by carry-over members, ratchet and pawl advancing means to cause a predetermined displacement of the input member of each stage, the output member of the stage of highest order being engaged with the carriage, means to operate said advancing means in successive selected combinations to advance said carriage, and return means including means to cause all advancing means to complete an even multiple of said displacment and means to return said carriage to its starting position, the pawl in said advancing means for the stage of highest order being adapted for deflection from its ratchet to allow the stages of lower order to remain stationary during said carriage return and for reengagement with its ratchet after said carriage return.

11. In type composing apparatus, the combination of a variably movable carriage for spacing characters, a variable escapement having a number of connected stages each comprising a differential having a direct input member and an output member, advancing means to cause a predetermined displacement of the input member of each stage, the output member of the stage of highest order being engaged with the carriage, means to operate said advancing means in successive selected combinations to advance said carriage, contact means for each stage, means secured to each output member to operate the contact means for each alternate movement of said member, and return means including a circuit connected with said contacts to cause all advancing means to complete an even multiple of said displacement.

12. In type composing apparatus, the combination of a variably movable carriage for spacing characters, a variable escapement having a number of connected stages each comprising a differential having a direct input mem ber and an output member, advancing means to cause a predetermined displacement of the input member of each stage, the output member of the stage of highest order being engaged with the carriage, means to operate said advancing means in successive selected combinations to advance said carriage, contact means for each stage, means secured to each output member to operate the contact means for each alternate movement of said member, and return means including a circuit connected with said contacts to cause all advancing means to complete an even multiple of said displacement and means to return said carriage to its starting position without moving the stages below said stage of highest order.

13. In type composing apparatus, the combination of a variably movable carriage for spacing characters, a variable escapement having a number of connected stages each comprising a differential having a direct input member and an output member, advancing means to cause a predetermined displacement of the input member of each stage, the output member of the stage of highest order being engaged with the carriage, means to operate said advancing means in successive selected combinations to advance said carriage, contact means for each stage, means secured to each output member to operate the contact means for each alternate movement of said member, and return means including a circuit connected with said contacts to cause all advancing means to complete an even multiple of said displacement and means to return said carriage to its starting position, the advancing means for the stage of highest order comprising a ratchet and a pawl adapted for deflection from the ratchet to allow the stages of lower order to remain stationary during said carriage return and for reengagement with the ratchet after said carriage return.

14. In type composing apparatus, the combination of a variably movable carriage for spacing characters, a variable escapement having a number of connected stages each comprising a differential having a direct input member and an output member, advancing means to cause a predetermined displacement of the input member of each stage, the output member of the stage of highest order being engaged with the carriage, means to operate said advancing means in successive selected combinations to advance said carriage by a distance corresponding to a justified line, and justification checking means comprising a circuit to cause a further advance of said carriage suflicient to cause all stages to reach even multiples of said displacement if the carriage has justified the line, and

10 means to indicate the condition in which any stage fails to reach an even multiple of said displacement.

15. In type composing apparatus, the combination of a variably movable carriage for spacing characters, a variable escapement having a number of connected stages each comprising a differential having a direct input member and an output member, advancing means to cause a predetermined displacement of the input member of each stage, the output member of the stage of highest order being engaged with the carriage, means to operate said advancing means in successive selected combinations to advance said carriage by a distance corresponding to a justified line, means to cause a further advance of said carriage suflicient to cause all stages to reach even multiples of said displacement if the carriage has justified the line, means to indicate the condition in which any stage fails to reach an even multiple of said displacement, and return means including means operative to cause any stage failing to reach said even multiple to advance and means to return said carriage to its starting position, the advancing means for the stage of highest order comprising a ratchet and a pawl adapted for deflection from the ratchet to allow the stages of lower order to remain stationary during said carriage return and for reengagement with the ratchet after said carriage return.

16. Character spacing means for type composition having, in combination, a spacing carriage and variable escapement apparatus, said apparatus including a plurality of individually cyclically operable space entry means, a mechanism operatively associated with said space entry means and connected with said carriage, said mechanism being adapted to cause variable movements of said carriage corresponding to the operated combination of said space entry means, means operative by selective operation of said space entry means to advance each of said space entry means from a starting position to advance said carriage from an accurately predetermined initial position intermittently by spaces corresponding to the characters in a line, means operative at the completion of the spacing of said line to complete a cycle in each of said space entry means to advance the carriage to a total displacement equal to a multiple of a plurality of the smallest spaces produced by the space entry means, and means engageable with the carriage and operative to return it by said total displacement to said initial position.

17. The combination according to claim 16, with indicating means to detect and indicate the absence of any space entry means from said starting position.

18. The combination according to claim 16, wherein said means operative at the completion of the spacing of said line include means to cause the space entry means to move said carriage a predetermined distance related to the justified line length, whereby the carriage reaches a position for which each space entry means has completed a cycle it the line is justified, and indicating means to detect and indicate the failure of any stage to complete its cycle.

19. Character spacing means for type composition having, in combination, a spacing carriage and variable escapement apparatus, said apparatus including a plurality of stages mutually interconnected in progressive numerical order, an output stage other than the stage of lowest order having a connection to said carriage, each stage having an independently movable input member adapted to advance continually in one direction with means to move said member to advance the stage intermittently in discrete movements each representing a space corresponding to the numerical order of the stage, each stage having an output member having a starting position reached after an integral number of said discrete movements, the movements of said stages producing a cumulatively additive movement in said carriage, means operative by selective movement of the input members of said stages to move said carriage from an initial position intermittently by spaces corresponding to the characters in a 11 line, means operative at the completion of the spacing of said line to cause each output member to complete said integral number of discrete movements and advance to said starting position, and means engageable with the carriage and operative to move it a distance equal to a multiple of the space corresponding to a movement of the output stage to return the carriage to said initial position.

20. The combination according to claim 19, with indicating means to detect and indicate the absence of any stage from said starting position.

21. The combination according to claim 19, wherein said means operative at the completion of the spacing of said line include means to cause the input members of said stages to move said carriage a predetermined distance related to the order of said output stage and to the justified line length, whereby the carriage reaches a position for which each input member is in its starting position if the line is justified, and indicating means to detect and indicate the absence of any stage from said starting position.

22. The combination according to claim 19, with indicating means to detect and indicate the absence of any stage from said starting position, and means having provision to advance any stage not in said starting position thereto.

23. Character spacing means for type composition having, in combination, a spacing carriage and variable escapement apparatus including a plurality of stages mutually interconnected in progressive numerical order, an output stage other than the stage of lowest order having a connection to said carriage, each stage having independent input means adapted to advance continually in one direction and cyclically actuable output means to advance the stage intermittently in discrete movements each representing a space corresponding to the numerical order of the stage, the movements of said stages producing a cumulatively additive movement in said carriage, means operative by selective actuation of said input means to move said carriage from an initial position intermittently by spaces corresponding to the charatcers in a line, means operative at the completion of the spacing of said line to actuate the stages to complete a cycle therein, and means engageable with the carriage and operative to move it a distance equal to a multiple of the space corresponding to a movement of the output stage to return the carriage to said initial position.

24. Character spacing means for type composition having, in combination, a spacing carriage and variable escapement apparatus, said apparatus including a plurality of stages mutually interconnected in progressive numerical order, an output stage other than the stage of lowest order having a connection to said carriage, each stage having an independently rotatable input member and an output member with means to rotate said input member to advance the stage intermittently in discrete movements each representing a space corresponding to the numerical order of the stage, said output member having an integral number of movements in a complete cycle of rotation, the movements of said stages producing a cumulatively additive movement in said carriage, means operative by selective rotation of the input members of said stages to move said carriage from an initial position intermittently by spaces corresponding to the characters in a line, means operative at the completion of the spacing of said line to complete a cycle of rotation of each output member, and means engageable with the carriage and operative to move it a distance equal to a multiple of the space corersponding to a movement of the output stage to return the carriage to said initial position.

25. In type composition, the method of advancing a spacing carriage from and returning it to an accurately predetermined marginal position, which includes the steps of engaging the carriage with a spacing mechanism adapted to advance it by any one of a plurality of multiples of a predetermined increment, operating the mechanism to advance the carriage from said marginal position in a succession of character spacing movements to reach a total displacement which may or may not be evenly divisible by a given relatively large multiple available in the spacing mechanism, returning the carriage to the marginal position while restraining the mechanism from reverse movement, and repeating the foregoing steps, the mechanism being further advanced after said succession of character spacing movement and before said repetition to cause it to complete a total displacement which is evenly divisible by said relatively large multiple of said increment.

26. The method according to claim 25, in which. the total of the succession of character spacing movements equals a selected justified line length, and the further advancement of the mechanism is predetermined by said justified line length and said given relatively large multiple of said increment.

27. The method according to claim 25, in which the total of the succession of character spacing movements equals a selected justified line length and the further advancement of the mechanism is predetermined by said justified line length and said given relatively large multiple of said increment, and further including the step of detecting and indicating any failure of said mechanism to complete a whole number of said given multiple of the predetermined increment.

28. The method according to claim 25, in which the total of the succession of character spacing movements equals a selected justified line length and the further advancement of the mechanism is predetermined by said justified line length and said given relatively large multiple of said increment, and further including the step of detecting and indicating any failure of said mechanism to complete a whole number of said given multiple of the predetermined increment, and further advancing the carriage after indicating suchfailure to complete said whole number.

29. Mechanism for advancing a carriage in a succession of variable increments from and returning it to a starting position, said mechanism having, in combination, a plurality of stages each having a device movable in equal steps and independent means for causing the device to move one step at a time in a normal forward direction, a gear train connecting the stages in an ascending ratio of cumulative movements corresponding to a numerical progression, the highest stage in the progression being connected to the carriage to cause it to ad vance when any one or more stages moves and having overrunning means to permit return movement of the carriage to the staring position with each lower stage maintained in fixed position, and means connected to the stages and selectively operated by numerical coding to cause them to move in combinations by which the carriage is advanced in said succession of increments, said last-mentioned means including a control operable after the final increment to cause each stage to complete a multiple of the number of steps representing the base in said numerical progression.

30. Mechanism for advancing a carriage in a succession of variable increments from and returning it to a starting position, said mechanism having, in combination, a plurality of stages each having a toothed escapement wheel and independent means for causing the wheel to escape a tooth at a time in a normal forward direction, a gear train connecting the stages in an ascending gear ratio corresponding to a numerical progression, the highest stage in the progression being connected to the carriage to cause it to advance when any one or more stages escapes and having overrunning means to permit return movement of the carriage to the starting position with each lower stage maintained in fixed position, and means connected to the stages and selectively operated by numerical coding to cause them toescape-incornbinations by which the carriage is advanced in said succession of increments, said last-mentioned means including a control operable after the final increment to cause each stage to complete the escapement of a multiple of the number of teeth representing the base in said numerical progression.

31. Mechanism for advancing a carriage in a succession of variable increments from and returning it to a starting position, said mechanism having, in combination, a plurality of stages each having a toothed escapement wheel and independent means for causing the wheel to escape a tooth at a time in a normal forward direction, a gear train connecting the stages in a binary progression, the highest stage in the progression being connected to the carriage to cause it to advance when any one or more stages escapes and having overrunning means to permit return movement of the carriage to the starting position with each lower stage maintained in fixed position, and means connected to the stages and selectively operated by binary coding to cause them to escape in combinations by which the carriage is advanced in said succession of increments, said last-mentioned means including a control operable after the final increment to cause each stage to complete the escapement of an even number of teeth.

32. Character spacing means for type composition having, in combination, a spacing carriage, variable spacing apparatus engageable with the carriage and including nonreversing means arranged to displace the carriage by any one of a plurality of multiples of a unit space, means to operate said apparatus to advance the carriage from an accurately predetermined initial position by variable displacements corresponding to the widths of characters in a line to space said line, whereby the total displacement may or may not be evenly divisible by a given relatively large multiple available in said non-reversing means, means operative at the completion of the spacing of said line to operate said apparatus to advance the carriage until said total displacement becomes evenly divisible as aforesaid, and means engageable with the carriage and operative to return it by said evenly divisible total displacement to said initial position while restraining said non-reversing means.

33. The combination according to claim 32, with indicating means to detect and indicate the absence of the carriage from a position corresponding to a total displacement evenly divisible by a given relatively large multiple available in the non-reversing means.

34. The combination according to claim 32 with indi cating means to detect and indicate the absence of the carriage from a position corresponding to a total displacement evenly divisible by a given relatively large multiple available in the non-reversing means, and means to 0perate the escapement apparatus to advance the carriage until the total displacement becomes evenly divisible as aforesaid if said indicating means detect said absence.

References Cited by the Examiner UNITED STATES PATENTS 421,838 2/1890 McLaughlin 197'68 1,048,265 12/ 1912 Alexander 197-82 1,998,848 4/1935 Schmitt 197-192 X 2,262,676 11/ 1941 Helmond 197-120 X 2,385,036 9/1945 Smathers 19784.3 2,541,295 2/1951 Sagner 19766 ROBERT E. PULFREY, Primary Examiner. 

1. A VARIABLE ESCAPEMENT MECHANISM HAVING, IN COMBINATION, A NUMBER OF STAGES ARRANGED IN A SERIES, EACH STAGE COMPRISING A DIFFERENTIAL DEVICE HAVING TWO INPUT MEMBERS AND AN OUTPUT SHAFT, AT LEAST ONE OF SAID STAGES HAVING AN INPUT MEMBER CONNECTED WITH THE OUTPUT SHAFT OF THE PRECEDING STAGE IN SAID SERIES, ESCAPEMENT MEANS TO ADVANCE AN INPUT MEMBER OF EACH STAGE BY EQUAL INTERMITTENT MOVEMENTS, CONTACT MEANS FOR EACH STAGE, AND MEANS SECURED TO EACH OUTPUT SHAFT TO OPERATE THE CONTACT MEANS FOR EACH ALTERNATE MOVEMENT OF SAID SHAFT, SAID CONTACT MEANS FORMING A CLOSED SERIES CIRCUIT WHEN THE STAGES ARE EACH SIMULTANEOUSLY IN ONE PREDETERMINED ALTERNATE DISPLACEMENT, AND EACH CONTACT MEANS FORMING A CONNEKCTION FROM SAID SERIES CIRCUIT TO ITS ESCAPEMENT MEANS WHEN ITS CORRESPONDING STAGE IS NOT IN SAID PREDETERMINED ALTERNATE DISPLACEMENT. 